3000 psi cylinders deliver >40% more oxygen than 2000 psi cylinders. UltraFill's long-lasting 3,000 PSI cylinders (MB08, MC13, MD22, ME36) provide patients with greater than 40% more oxygen than similar sized 2,000 PSI tanks. That means a patient using the 3,000 PSI MB08 tank on a setting of two at 20 BPM will have approximately three more hours of oxygen than the patient using a 2,000 PSI M6 tank on the same settings.